Another study has reported that up‐regulated SMAD7 has the positive correlation with BCL2 that is the anti‐apoptotic gene in gastric epithelial cells, and the activation of transforming growth factor‐β1 (TGF‐β1), type II TGFβ receptor, p‐smad2/3, SMAD4 and SMAD7 axis activated by SAMC promotes the expression of BCL2, inhibiting the apoptosis of cancer cells.40, 41. This evidence concerns the gene SMAD4 and cancer.